Compilare: main.cpp: In function 'void PLUS(int, int)': main.cpp:18:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v[nod].size(); ++i) { ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void MINUS(int, int)': main.cpp:28:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < v1[nod].size(); ++i) { ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'void CTC()': main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int y = 0; y < ctc[k].size() && ok; ++y) { ~~^~~~~~~~~~~~~~~ main.cpp:71:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i1 = 0; i1 < ctc[i].size() && (!muchie[i][j] || !muchie[j][i]); ++i1) { ~~~^~~~~~~~~~~~~~~ main.cpp:72:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j2 = 0; j2 < ctc[j].size() && (!muchie[i][j] || !muchie[j][i]); ++j2) { ~~~^~~~~~~~~~~~~~~ main.cpp:36:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^ main.cpp: In function 'int main()': main.cpp:112:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("graf2.in", "r", stdin); ^ main.cpp:113:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("graf2.out", "w", stdout); ^ main.cpp:114:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^